In a report by the National Academies Press entitled Engineering in K-12 Education: Understanding the Status and Improving the Prospects, the authors state that because of its hands-on and applied nature, teaching engineering to younger students may be a good way to encourage STEM participation (National Academy of Engineering & National Research Council, 2009). While there are undoubtedly many factors that contribute to effective learning and teaching in engineering, one factor that shows promise for improving STEM instruction in the classroom is the use of comparison to highlight key concepts (Gentner, et al., in press; Jee et al., 2010; Rittle-Johnson & Star, 2007).

The current study explores the relationship between two spatial learning tools that can provide cues to comparison--spatial alignment and gesture. The study is based on prior research of museum laboratory classroom lessons on building strong bridges. During the initial study we found that overlaying triangles on larger structures promoted more learning than a No Overlay condition. In the museum classroom study we noticed that the instructor sometimes produced tracing gestures over the triangular structures, which may also have provided valuable information about the importance of triangular bracing. However, there was not enough variation in his gesture to explore this possibility.

Figure 1. Graphical representation of the 2(Overlay: Overlay, No Overlay) x 2(Gesture: Gesture, No Gesture) design used in Studies 1a and 1b.

In order to address the question of how gesture and spatial alignment might work together to promote learning of the triangular brace principle, we conducted two laboratory studies that systematically manipulated these learning tools. In Study 1a we tested forty-two 6-9 year-old children using a 2(Overlay: Overlay, No Overlay) x 2(Gesture: Gesture, No Gesture) design to explore the possible benefit of adding gesture to instruction that included spatial alignment through overlay. (See Figure 1.) Children were administered pre-test questions asking them how they would make a set of structures stable (e.g. bridge, bunk bed). After the pre-test, children watched two videos. The first video provided basic information about bridges. The second video, which was presented in one of the four experimental conditions, focused on why triangles are stable. Children then had the opportunity to build a bridge using a set of Uberstix®. Following the bridge activity, experimenters administered post-test. See Figure 2 for pre- and post-test performance by condition. In Study 1a, all children learned, but they learned less in the gesture conditions (Gesture Only: Mimprove =.33, SD=.35, Overlay+Gesture: Mimprove =.27, SD=.43) than in the Control condition (Mimprove =.42, SD=.34) and Overlay Only condition (Mimprove =.55, SD=.33). The difference between the gesture conditions and the control was significant, controlling for age, gender, and pre-test: ß=-1.85, p < .01. In reviewing the videos, we realized that the instructor’s gestures were produced very quickly and may have been difficult to process or may have even been confusing.

Figure 2. Pre- and Post-test scores across the four conditions for Study 1a.

This led to Study 1b, where we used the exact same protocol, but slowed down the gesture. Figure 3 displays pre- and post-test results from Study 1b. Once again, all children improved; however, with slower gesture, children in the gesture conditions improved more (Gesture Only: Mimprove =.51, SD=.33, Overlay+Gesture: Mimprove =.49, SD=.33) than children in the Control condition (Mimprove =.38, SD=.30). Further, children in the Overlay Only condition did not significantly differ from those in the Control condition (M=.36, SD=.38), as was also the case in Study 1a.

Figure 3. Pre- and Post-test performance for Study 2b.

Strikingly, in Study 1b 96 of the 111 children scored a 0 or a 1 (out of 4) at pre-test, showing low knowledge of the diagonal brace principle. When we analyzed children with low prior knowledge separately from children with higher prior knowledge, we found that children with low prior knowledge benefited more from slow, deliberate gestures (M=.66, SD=.37 in the Gesture Only and M=.62, SD=.33 in the Gesture+Overlay condition) than Control (M=.41, SD=.34) and Overlay Only (M=.43, SD=.41) conditions. On the other hand, children with higher levels of prior knowledge at pretest did not benefit more from gesture, possibly because of their near ceiling performance at pretest (Control: M=.92, SD=.10, Overlay Only: M=.58, SD=.59, Gesture Only: M=.90, SD=.16; Overlay+Gesture=.75, SD=.35) (See Figure 4) The positive effect of gesture for low prior knowledge children was confirmed using a hierarchical logistic regression with controls for age and gender, ß=.85, p=.002. Effects of Overlay, and the interaction between Overlay and Gesture were not significant (ß=-.56, p=.64; ß=.62, p=.67, respectively).

Figure 4. Post-test performance by prior knowledge for Study 2b.

Slower gesture may encourage learning by highlighting the relationship between individual components common to both triangles and larger structures. Interestingly, the Gesture+Overlay condition did not differ from the Gesture Only condition in either Study 1a or 1b. This suggests that the effect of gesture, whether it hinders or promotes learning, may be a stronger cue to comparison than overlay in the one-on-one situation afforded by the laboratory studies.

Of note, performance of children in the Control and Overlay Only conditions did not differ in the lab studies even though Overlay promoted more learning in the museum classroom study. This discrepancy highlights the fact that findings in the lab may not directly transfer to the classroom. Overlay may be helpful in the busy, distracting classroom environment, but may be superfluous in the quieter, controlled laboratory environment where it is easier for children to attend to instruction. Similarly, although we found no difference between Gesture and Gesture+Overlay conditions in the laboratory, it is still possible that the combination of these two learning tools may promote more robust learning in the classroom.

♦ National Academy of Engineering & National Research Council. (2009). Engineering in K-12 education: Understanding the status and improving the prospects. Washington, DC: The National Academies Press.